*{
    margin: 0;
    padding: 0;
    border: 0;
}

.num-list{
    margin-left: 100px;
    margin-top: 100px;
    border: 1px solid black;
    width: 200px;
    height: 400px;
    overflow: scroll;
    display: inline-block;
}

.num-list-item{
    width: 198px;
    height: 20px;
    line-height: 20px;
}

.num-list-item:not(:first-child){
    border-top: 1px solid green;
}